1. Field of the Invention
The present invention relates generally to lighting fixtures and, more particularly, to a new and improved proximity sensor housing and an adjustable mast arm for an outdoor lighting fixture for mounting a pair of flood lights or the like.
2. Description of the Prior Art
Outdoor flood lights have been known for many years. In such devices, it is common to provide a mechanism in the mounting whereby the direction of the light may be adjusted at least to a limited degree. A common manner in which this is accomplished is by providing a connection between the fight fixture and the base by which the fixture may be moved relative to the base and then secured against further motion.
U.S. Pat. No. 4,333,132, issued to Paley, discloses a manually controlled, environmentally sealed swivel unit for use in an adjustable lighting fixture. The swivel unit comprises a base, a housing, a swivel ball device and a means for controlling the rotation of the swivel ball. This arrangement allows the swivel ball to rotate about a first axis and also to rotate about the second axis perpendicular to the first axis. The swivel unit further includes a tension means for forcing the swivel ball controller against the swivel ball device to define a predetermined lamp holding force.
The Denison patent (U.S. Pat. No. 5,086,379) and the Snyder patent (U.S. Pat. No. 3,278,203) disclose two additional examples of swivel or ball-and-socket type joints used in lighting fixtures.
However today, many lighting fixtures also include a proximity sensor which is operable to actuate the light for variable or fixed amounts of time when an object is detected in the path of the sensor. Certain problems have been encountered in incorporating a successful proximity sensor-into flood lights. One problem is that the sensor housing must be movable over a wide number of positions in order to focus on a selected area of interest. Another problem is that the sensor must be off-set from the lamps in order to avoid heat build-up from the lamps which will cause the sensor to fail prematurely. A final problem is that the sensor housing must either be water tight or allow water to escape from the housing in order to protect the electronics associated with the sensor.
Various solutions have been tried to overcome these problems. In one early approach, the sensor housing was off-set from the lighting fixture base by a length of tubing having ball-and-socket joints located at each of its ends. This approach does off-set the housing from the heat of the lights. However, the ball-and-socket joints are limited to about a 60.degree.-90.degree. field of rotation. Accordingly, this design limits the positioning of the sensor. In addition, the path through the ball-and-socket for the electrical leads to power the sensor is a natural conduit for water to enter the housing and damage the electronics in the housing.
Another approach which has been moderately successful is an inverted L-shaped bracket attached to the base of the lighting fixture and downwardly extending to off-set the sensor from the area around the heat of the lights. The inverted L-shaped bracket includes a horizontal swivel portion located midway along the bracket and a 180.degree. pivotable joint located at the end of the bracket opposite the end attached to the base. Such an arrangement does avoid the heat of the lights but provides only limited positioning along two axes for positioning the sensor. In addition, the L-shaped bracket still provides a path for water to enter the sensor housing, thereby possibly damaging the electronics housed therein.
Thus, there remained a need for a new and improved sensor housing having an adjustable mast arm for a swivel lighting fixture which is operable to position the sensor housing away from the heat of the lamps and provide a high degree of flexibility for positioning the sensor while, at the same time, eliminating the danger of water entering and damaging the electronics enclosed in the sensor housing.